Architectural structural panels are attached to building walls of all types to cover inner wall structures and beautify or augment the external or interior appearance of building walls. The manner of attachment of the panels to walls can be expensive, and in some cases the attachment can be more expensive than the panels themselves. In the current commercial building market, building designers prefer panel installations that show no fasteners, but rather show crisp, clean joint lines. Installers must be able to size the panels readily and form joints that are properly located and cleanly formed.
An ideal structural panel is lightweight and relatively inexpensive to manufacture, has good insulation value, and resistant to wear. Panels that are durable, weather-resistant, and have high compressive and shear strength are particularly useful for outdoor applications. Structural panels having metal face sheets laminated with a plywood or wood composite core have been used, but are known to have the problem of being vulnerable to damage from moisture which can seep into the wood core. Honeycomb cores of plastic or metal material laminated between metal face sheets are strong and water-resistant, but have high fabrication costs. Structural panels with metal face sheets laminated to a core of foam or solid polyethylene provide a combination of advantages. For example, a laminate may be formed using the improved sheet bonding process developed by the present inventor, as described in U.S. Pat. No. 5,114,510 for "Method of Forming a Lightweight Structural Panel", issued on May 19, 1992.
A further improved structural panel having metal face sheets bonded to a plastic core body formed by two outer liner sheets fusion-bonded to an inner corrugated plastic sheet was also developed by the present inventor, as described in U.S. Provisional application Ser. No. 60/051178, filed on Jun. 28, 1997, and formal U.S. patent application Ser. No. 08/958,340, filed on Oct. 27, 1997, entitled "Structural Panels With Metal Faces and Corrugated Plastic Core", which are incorporated herein by reference. These corrugated-core panels have excellent strength-to-weight properties and resistance to weathering.
Current panel installation systems in widespread use require panels to be cut to size, and the panel edges to be fabricated or bent and fastened in metal extrusion channels or rails which are mounted along the boundaries of the panels. It is often difficult to securely hold a panel in place without shifting or buckling relative to adjacent panels, thereby degrading the clean appearance of the joints. Also, panels having plastic core materials as are commonly used today do not have suitable landing areas that allow caulk to adhere cleanly to the panel edges at a joint.
It is therefore a principal object of the present invention to provide for mounting a structural panel to a wall in a manner that is efficient and inexpensive, and that will hold a panel securely in place so that it does not shift or buckle relative to adjacent panels or degrade the clean appearance of the joints.
It is a specific object to provide for mounting a preferred type of structural panels having corrugated plastic cores, and also to implement the mounting in a manner which allows caulk to adhere cleanly to THE panel edges at the joints. A further object is to provide a mounting device and method which is easy to use for panel installation, and which is completely hidden from view of the front side of the panel. Yet another object is to provide a mounting device and method for forming hair line joints which is easy to use and which allows the panels to move with respect to each other for normal expansion and contraction of the wall.